Related papers: Self-Organizing Neutrino Mixing Matrix
In the minimal standard electroweak gauge model, there is an effective dimension-five operator which generates neutrino masses, and it has only three tree-level realizations. One is the canonical seesaw mechanism with a right-handed…
We propose an inverse seesaw model with large $SU(2)_L$ multiplets applying modular $A_4$ symmetry where $SU(2)_L$ quartet and septet fermions are introduced as triplets under the symmetry. The neutral components of the quartet contribute…
We study the lepton sector in the model based on the local gauge group $SU(3)_c\otimes SU(3)_L\otimes U(1)_X$ which do not contain particles with exotic electric charges. The seesaw mechanism and discrete $A_4$ symmetry are introduced into…
Generation of neutrino mass in SO(4) model is proposed here. The algebraic structure of SO(4) is same as to that of $SU(2)_{L}\times SU(2)_{R}$. It is shown that the spontaneous symmetry breaking results three massive as well as three…
We discuss a neutrino mass model based on the S_4 flavor symmetry within the minimal seesaw framework, in which only two right-handed neutrinos are introduced and transform as 2 under S_4. Although the model contains less free parameters…
A convincing explanation of the smallness of neutrino masses is represented by the Type-I Seesaw mechanism, where the two measured neutrino mass differences can be generated by introducing at least two right-handed neutrinos. In an…
We explore the possibility of interpreting the solar and atmospheric neutrino data within the context of the Minimal Supersymmetric Standard Model augmented by a single U(1) anomalous family symmetry spontaneously broken by non-zero vacuum…
We consider the see-saw mechanism for hierarchical Dirac and Majorana neutrino mass matrices m_D and M_R, including the CP violating phases. Simple arguments about the structure of the neutrino mass matrix and the requirement of successful…
We adopt a bottom-up approach to reconstruct the possible neutrino mass matrix patterns, in the hypothesis that $\lambda = \sin \theta_C$, where $\theta_C$ is the Cabibbo angle, is a useful expansion parameter in the neutrino sector as it…
In a wide class of unified models there is an additional (and possibly dominant) term in the neutrino mass formula that under the simplest assumption takes the form M_{\nu} = (M_N + M_N^T)u/M_G, where M_N is the neutrino Dirac mass matrix,…
Status of determination of the neutrino masses and mixing is formulated and possible uncertainties, especially due to presence of the sterile neutrinos, are discussed. The data hint an existence of special ``neutrino'' symmetries. If not…
On the basis of the so-called "yukawaon" model, we found out a special form of the neutrino mass matrix $M_\nu$ which gives reasonable predictions. The $M_\nu$ is given by a multiplication form made of charged lepton mass matrix $M_e$ and…
We consider various possibilities for generating neutrino masses in supersymmetric models with an additional U(1)' gauge symmetry. One class of models involves two extra U(1)' x U(1)'' gauge symmetries, with U(1)'' breaking at an…
We propose a flavour model based on an $A_4$ symmetry combined with a type-II seesaw mechanism for neutrino mass generation. The resulting neutrino mass matrix obeys a sum rule that, together with the measured mass-squared differences,…
We propose a $U(1)_L$ model with $A_4$ symmetry in light of the linear seesaw for majorana neutrino that capable of generating the current lepton and quark mass and mixing patterns. The smallness of Majorana neutrino mass is reproduced…
We suggest the fermion doubling for all quarks and leptons. It is a generalization of the neutrino doubling of the seesaw mechanism. The new quarks and leptons are $SU(2)$ singlets and carry the electromagnetic charges of their lighter…
In the first part of the talk, three key ideas proposed in the 1970s, and in particular their combined role in providing an understanding of the neutrino-masses as well as of the baryon-asymmetry of the universe, are expounded. The ideas in…
The Type I, II and hybrid (I+II) seesaw mechanism, which explain why neutrinos are especially light, are consequences of the left-right symmetric model (LRSM). They can be classified by the ranges of parameters of LRSM. We show that a…
Assuming the existence of an eV or KeV scale sterile neutrino, we develop a 3+1 neutrino mass model using $A_4\times Z_4 \times Z_2$ symmetry group. Three Higgs $H, H^{\prime}$ and $H^{\prime\prime}$ are considered to give a desired…
The prediction of small neutrino masses through the Seesaw Mechanism and their subsequent measurement suggests that the natural cut-off of the Standard Model is very high indeed. The recent neutrino data must be interpreted as a reflection…